[EricH]

Who owns the tools? If they're school property, then you would, of course, need permission to take them for non-school uses (robotics competitions presumably being a school use). Otherwise, the school could, if it so desired, pursue theft charges.

However, if the tools are team-owned, and you're worried about the safety of the tools if they are stored at school, members who are not graduating/leaving the team would be a pretty good choice. There is, however, one caveat that should be applied: If they don't bring them back in good working order in time for build season, they buy a replacement for the team. It might be good to get agreement to this in writing.

You could also suggest buying personal tools for personal projects, and robotics can't "borrow" those. Admittedly, this can be expensive, but it doesn't have to be.

Or, perhaps better, find out, from the powers that be at the school, what the procedure is for gaining access to the robotics area during times when school is completely closed (i.e., breaks). If you can work within that procedure, then you can check on things whenever somebody needs to check out a tool for a side project/robotics project. (And by check out, I mean: Write down your name, contact info, and tools you have on a sheet of paper and leave it with the other tools, then indicate when you return them.) If something is missing that isn't checked out, then you check the team members. If they don't have it, contact the authorities, starting at the school level. (If I were principal, I'd want to know that someone was in the building that shouldn't have been there.)